Hippolytus Proves that Irenaeus' Original Work (Against All Heresies) Only Dealt with the Valentinians and Marcosians

It's as plain as day, my friends. I can't believe other scholars haven't noticed this. Hippolytus mentions Irenaeus twice in his Refutations of All Heresies. The first is when Hippolytus draws from his description of the Marcosians:

For also the blessed presbyter Irenaeus, having approached the subject of a refutation in a more unconstrained spirit, has explained such washings and redemptions, stating more in the way of a rough digest what are their practices. (And it appears that some of the Marcosians,) on meeting with (Irenaeus' work), deny that they have so received (the secret word just alluded to), but they have learned that always they should deny. [Ref. Her vi. 37]

The second time appears at the end of Book Six when he writes:

These assertions, then, those who are of the school of Valentinus advance concerning both the creation and the universe, in each case propagating opinions still more empty ... And inasmuch as these statements are trifling and unstable, it does not appear to me expedient to bring them before (the reader. This, however, is the less requisite,) as now the blessed presbyter Irenaeus has powerfully and elaborately refuted the opinions of these (heretics). And to him we are indebted for a knowledge of their inventions, (and have thereby succeeded in) proving that these heretics, appropriating these opinions from the Pythagorean philosophy, and from over-spun theories of the astrologers, cast an imputation upon Christ, as though He had delivered these (doctrines). But since I suppose that the worthless opinions of these men have been sufficiently explained, and that it has been clearly proved whose disciples are Marcus and Colarbasus, who were successors of the school of Valentinus, let us see what statement likewise Basilides advances.[Ref. Her. vi.50]

Will someone please explain to me why - if Hippolytus' copy of Irenaeus had the section dealing with all the other heretics deriving from Simon including the Bsilideans - why isn't Irenaeus cited here and in any of the other heresies dealing with these sects.

The answer is clear. Chapters 23 - 31 were not a part of Irenaeus' original treatise. Hippolytus would have referenced Irenaeus there too. Chapters 23 - 31 were added later by someone trying to reconcile their two systems.